Device and method for controlling backlight, and display device

Patent metadata

Field	Value
Publication number	US-11367404-B2
Application number	US-202016820246-A
Country	US
Kind code	B2
Filing date	Mar 16, 2020
Priority date	Jul 4, 2019
Publication date	Jun 21, 2022
Grant date	Jun 21, 2022

Abstract

Embodiments of the present disclosure provide a device and a method for controlling backlight, and a display device. The device for controlling backlight, comprising: a first controlling circuit configured to receive a first power supply signal for controlling a display device to be turned on or off, and generate an output signal for causing a backlight module of the display device to be turned off, in response to the first power supply signal being in a first status for controlling the display device to be turned off; and a second controlling circuit configured to receive the first power supply signal, and generate an output signal for causing the backlight module to be turned on again after being kept in a turned off state for a predetermined time period, in response to the first power supply signal being in a second status for controlling the display device to be turned on.

First claim

We claim:

1. A device for controlling backlight, comprising:
a first controlling circuit configured to receive a first power supply signal for controlling a display device to be turned on or off, and generate an output signal for causing a backlight module of the display device to be turned off, in response to the first power supply signal being in a first status for controlling the display device to be turned off; and
a second controlling circuit having a different circuit structure than the first controlling circuit, and being configured to receive the first power supply signal, and generate an output signal for causing the backlight module to be turned on again after being kept in a turned off state for a predetermined time period, in response to the first power supply signal being in a second status for controlling the display device to be turned on,
wherein the first controlling circuit comprises:
a second capacitor, wherein a first electrode of the second capacitor is electrically coupled to a third node, and a second electrode of the second capacitor is grounded; and
a third resistor, wherein a first terminal of the third resistor is electrically coupled to the third node, and a second terminal of the third resistor is electrically coupled to a controlling electrode of a second transistor,

wherein the second controlling circuit comprises:
a third capacitor, wherein a first electrode of the third capacitor is directly connected to a first power supply signal terminal for providing the first power supply signal, and a second electrode of the third capacitor is directly connected to a fourth node;
a fourth resistor, wherein a first terminal of the fourth resistor is directly connected to the fourth node, and a second terminal of the fourth resistor is grounded; and
a third transistor, wherein a controlling electrode of the third transistor is directly connected to the fourth node, a first electrode of the third transistor is grounded, and a second electrode of the third transistor is directly connected to a first outputting terminal for outputting the output signal.

2. The device of claim 1 , wherein the first controlling circuit further comprises:
a first diode, wherein a first electrode of the first diode is electrically coupled to a first power supply signal terminal for providing the first power supply signal, and a second electrode of the first diode is electrically coupled to a first node;
a first capacitor, wherein a first electrode of the first capacitor is electrically coupled to the first node, and a second electrode of the first capacitor is grounded;
a first transistor, wherein the controlling electrode of the first transistor is electrically coupled to a second node, a first electrode of the first transistor is electrically coupled to the first node, and a second electrode of the first transistor is electrically coupled to the third node;
a first resistor, wherein a first terminal of the first resistor is electrically coupled to the first power supply signal terminal, and a second terminal of the first resistor is electrically coupled to the second node;
a second resistor, wherein a first terminal of the second resistor is electrically coupled to the third node, and a second terminal of the second resistor is grounded; and
the second transistor, wherein a controlling electrode of the second transistor is electrically coupled to the third node, a first electrode of the second transistor is grounded, and a second electrode of the second transistor is electrically coupled to a first outputting terminal for outputting the output signal.

3. The device of claim 2 , wherein the first transistor is a P-type transistor, and the second transistor is an N-type transistor.

4. The device of claim 1 , wherein the second controlling circuit comprises:
a fourth transistor, wherein a controlling electrode of the fourth transistor is electrically coupled to a fifth node, a first electrode of the fourth transistor is grounded, and a second electrode of the fourth transistor is electrically coupled to a sixth node;
a second diode, wherein a first electrode of the second diode is electrically coupled to the fifth node, and a second electrode of the second diode is electrically coupled to a first power supply signal terminal for providing the first power supply signal;
a fourth capacitor, wherein a first electrode of the fourth capacitor is electrically coupled to the fifth node, and a second electrode of the fourth capacitor is grounded;
a fifth transistor, wherein a controlling electrode of the fifth transistor is electrically coupled to the sixth node via a seventh resistor, a first electrode of the fifth transistor is grounded, and a second electrode of the fifth transistor is electrically coupled to a first outputting terminal for outputting the output signal;
a fifth resistor, wherein a first terminal of the fifth resistor is electrically coupled to the first power supply signal terminal, and a second terminal of the fifth resistor is electrically coupled to the fifth node;
a sixth resistor, wherein a first terminal of the sixth resistor is electrically coupled to the first power supply signal terminal, and a second terminal of the sixth resistor is electrically coupled to the sixth node; and
the seventh resistor, wherein a first terminal of the seventh resistor is electrically coupled to the sixth node, and a second terminal of the seventh resistor is electrically coupled to the controlling electrode of the fifth transistor.

5. The device of claim 1 , further comprising: a third controlling circuit configured to invert the output signal generated by the first controlling circuit and the second controlling circuit, and output an inverted output signal via a second outputting terminal of the device for controlling backlight.

6. The device of claim 5 , wherein the third controlling circuit comprises:
an eighth resistor, wherein a first terminal of the eighth resistor is electrically coupled to a second power supply signal terminal for providing a second power supply signal, and a second terminal of the eighth resistor is electrically coupled to a first outputting terminal for outputting the output signal;
a ninth resistor, wherein a first terminal of the ninth resistor is electrically coupled to the second power supply signal terminal, and a second terminal of the ninth resistor is electrically coupled to the second outputting terminal; and
a sixth transistor, wherein a controlling electrode of the sixth transistor is electrically coupled to the first outputting terminal, a first electrode of the sixth transistor is grounded, and a second electrode of the sixth transistor is electrically coupled to the second outputting terminal.

7. The device of claim 6 , wherein the third controlling circuit further comprises:
a third diode, wherein a first electrode of the third diode is electrically coupled to the second power supply signal terminal, and a second electrode of the third diode is electrically coupled to the first terminal of the eighth resistor and the first terminal of the ninth resistor;
a fifth capacitor, wherein a first electrode of the fifth capacitor is coupled to the second electrode of the third diode, and a second electrode of the fifth capacitor is grounded;
a tenth resistor, wherein a first terminal of the tenth resistor is electrically coupled to the first outputting terminal, and a second terminal of the tenth resistor is electrically coupled to the controlling electrode of the sixth transistor;
an eleventh resistor, wherein a first terminal of the eleventh resistor is electrically coupled to the controlling electrode of the sixth transistor, and a second terminal of the eleventh resistor is grounded; and
a voltage stabilizing diode,

Assignees

• Beijing Boe Display Tech Co
• Boe Technology Group Co Ltd

Inventors

• Wang Jianting
• Bu Zhanchang
• Li Shou
• Yan hengyu
• Hou Xiaokang

Classifications

• G09G3/36 Primary

  using liquid crystals · CPC title

• G09G2320/0247

  Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes · CPC title

• G09G2330/028

  Generation of voltages supplied to electrode drivers in a matrix display other than LCD · CPC title

• G09G3/3406 Primary

  Control of illumination source (illumination devices structurally associated with liquid crystal cells G02F1/1336) · CPC title